A versatile tool with many uses, the Adjustable Wrench or Adjustable Spanner was coined as the Crescent Wrench when it was created in the early 1900s because the Crescent Tool Company was the first to patent the design, and the brand name became synonymous with the tool.
The Crescent wrench is also called Bahco in Sweden because the Swedish company BAHCO manufactured the wrench there, and it has also been called “knucklebuster” because the jaws sometimes slips when you’re tightening or loosening and scrapes your knuckles at the nearest surface
There were four adjustable wrenches created by the Crescent Tool Company, and each has a different size and function, and they are single divided head wrenches, meaning that one half is fixed and one is movable; unlike monkey wrenches that have jaws perpendicular to the handle, these are nearly parallel with the handle with 15-degree angle for leverage.
The type of adjustable wrench can be identified based on length and jaw opening as well as whether they have a set of jaws on each end or just one set on one side,and just by the simple crescent-like design of it too.
When it comes to its size, the Crescent Wrench or Adjustable Spanner is commonly sized at 8-in to 24-in max, while 8-in to 12-in are whats mostly preferred for flexible use in many kinds of applications.